Two novel Sm and la metal-Organic frameworks suggesting the reductive coupling of carbon dioxide (CO2) to oxalate (C2O42-): {[Ln(HPIDC)·(μ4-C2O4)0.5·H2O].2H2O}n·(Ln=Sm or La)

Abstract

Complexes formulated as {[Ln(HPIDC)(μ4-C2O4)0.5(H2O)]·2H2O}n [Ln=Sm or La; H3PIDC=2-(pyridin-4-yl)-1H-imidazole-4,5- dicarboxylic acid] have been synthesised under hydrothermal conditions. The complexes are both built up from T-shaped 3-connected HPIDC2- and 4-connected metal nodes and contain bridging oxalate (C2O42-) ligands, which might have been formed by the reductive coupling of CO2 molecules released from the HPIDC2- ligands through C-C bond cleavage.